Engineering cancer cell membranes with endogenously upregulated HSP70 as a reinforced antigenic repertoire for the construction of material-free prophylactic cancer vaccines

Immune cells distinguish cancer cells mainly relying on their membrane-membrane communication. The major challenge of cancer vaccines exists in difficult identification of cancer neoantigens and poor understanding over immune recognition mechanisms against cancer cells, particularly the combination among multiple antigens and the cooperation between antigens and immune-associated proteins. We exploit cancer cell membranes as the whole cancer antigen repertoire and reinforce its immunogenicity by cellular engineering to modulate the cytomembrane's immune-associated functions. This study reports a vaccine platform based on radiation-engineered cancer cells, of which the membrane HSP70 protein as the immune chaperon/traitor is endogenously upregulated. The resulting positive influences are shown to cover immunogenic steps occurring in antigen-presenting cells, including the uptake and the cross-presentation of the cancer antigens, thus amplifying cancer-specific immunogenicity. Membrane vaccines offer chances to introduce desired metal ions through membrane-metal complexation. Using Mn2+ ion as the costimulatory interferon genes agonist, immune activity is enhanced to further boost adaptive cancer immunogenicity. Results have evidenced that this artificially engineered membrane vaccine with favorable bio-safety could considerably reduce tumorigenicity and inhibit tumor growth. This study provides a universally applicable and facilely available cancer vaccine platform by artificial engineering of cancer cells to inherit and amplify the natural merits of cancer cell membranes. STATEMENT OF SIGNIFICANCE: The major challenge of cancer vaccines exists in difficult identification of cancer neoantigens and poor understanding over immune recognition mechanisms against cancer cells, particularly the combination among multiple antigens and the cooperation between antigens and immune-associated proteins. Cancer cell membrane presents superior advantages as the whole cancer antigen repertoire, including the reported and the unidentified antigens, but its immunogenicity is far from satisfactory. Cellular engineering approaches offer chances to endogenously modulate the immune-associated functions of cell membranes. Such a reinforced vaccine based on the engineered cancer cell membranes matches better the natural immune recognition pathway than the conventional vaccines.

Worth a Pound of Cure? Emerging Strategies and Challenges in Cancer Immunoprevention

Cancer immunoprevention applies immunologic approaches such as vaccines to prevent, rather than to treat or cure, cancer. Despite limited success in the treatment of advanced disease, the development of cancer vaccines to intercept premalignant states is a promising area of current research. These efforts are supported by the rationale that vaccination in the premalignant setting is less susceptible to mechanisms of immune evasion compared with established cancer. Prophylactic vaccines have already been developed for a minority of cancers mediated by oncogenic viruses (e.g., hepatitis B and human papillomavirus). Extending the use of preventive vaccines to non-virally driven malignancies remains an unmet need to address the rising global burden of cancer. This review provides a broad overview of clinical trials in cancer immunoprevention with an emphasis on emerging vaccine targets and delivery platforms, translational challenges, and future directions.

The Upper Nasal Space: Option for Systemic Drug Delivery, Mucosal Vaccines and "Nose-to-Brain"

Sino-nasal disease is appropriately treated with topical treatment, where the nasal mucosa acts as a barrier to systemic absorption. Non-invasive nasal delivery of drugs has produced some small molecule products with good bioavailability. With the recent COVID pandemic and the need for nasal mucosal immunity becoming more appreciated, more interest has become focused on the nasal cavity for vaccine delivery. In parallel, it has been recognized that drug delivery to different parts of the nose can have different results and for "nose-to-brain" delivery, deposition on the olfactory epithelium of the upper nasal space is desirable. Here the non-motile cilia and reduced mucociliary clearance lead to longer residence time that permits enhanced absorption, either into the systemic circulation or directly into the CNS. Many of the developments in nasal delivery have been to add bioadhesives and absorption/permeation enhancers, creating more complicated formulations and development pathways, but other projects have shown that the delivery device itself may allow more differential targeting of the upper nasal space without these additions and that could allow faster and more efficient programs to bring a wider range of drugs-and vaccines-to market.

Use of Iontophoresis Technology for Transdermal Delivery of a Minimal mRNA Vaccine as a Potential Melanoma Therapeutic

mRNA vaccines have attracted considerable attention as a result of the 2019 coronavirus pandemic; however, challenges remain regarding use of mRNA vaccines, including insufficient delivery owing to the high molecular weights and high negative charges associated with mRNA. These characteristics of mRNA vaccines impair intracellular uptake and subsequent protein translation. In the current study, we prepared a minimal mRNA vaccine encoding a tumor associated antigen human gp100_25-33 peptide (KVPRNQDWL), as a potential treatment for melanoma. Minimal mRNA vaccines have recently shown promise at improving the translational process, and can be prepared via a simple production method. Moreover, we previously reported the successful use of iontophoresis (IP) technology in the delivery of hydrophilic macromolecules into skin layers, as well as intracellular delivery of small interfering RNA (siRNA). We hypothesized that combining IP technology with a newly synthesized minimal mRNA vaccine can improve both transdermal and intracellular delivery of mRNA. Following IP-induced delivery of a mRNA vaccine, an immune response is elicited resulting in activation of skin resident immune cells. As expected, combining both technologies led to potent stimulation of the immune system, which was observed via potent tumor inhibition in mice bearing melanoma. Additionally, there was an elevation in mRNA expression levels of various cytokines, mainly interferon (IFN)-γ, as well as infiltration of cytotoxic CD8⁺ T cells in the tumor tissue, which are responsible for tumor clearance. This is the first report demonstrating the application of IP for delivery of a minimal mRNA vaccine as a potential melanoma therapeutic.

Immune-based combination therapy for esophageal cancer

Esophageal cancer (EC) is an aggressive malignancy raising a healthcare concern worldwide. Standard treatment options include surgical resection, chemotherapy, radiation therapy, and targeted molecular therapy. The five-year survival rate for all stages of EC is approximately 20%, ranging from 5% to 47%, with a high recurrence rate and poor prognosis after treatment. Immunotherapy has shown better efficacy and tolerance than conventional therapies for several malignancies. Immunotherapy of EC, including immune checkpoint inhibitors, cancer vaccines, and adoptive cell therapy, has shown clinical advantages. In particular, monoclonal antibodies against PD-1 have a satisfactory role in combination therapy and are recommended for first- or second-line treatments. Here, we present a systematic summary and analysis of immunotherapy-based combination therapies for EC.

Nasal route for vaccine and drug delivery: Features and current opportunities

Mucosal administration, and specifically nasal route, constitutes an alternative and promising strategy for drug and vaccine delivery. Mucosal routes have several advantages supporting their selective use for different pathologies. Currently, many efforts are being made to develop effective drug formulations and novel devices for nasal delivery. This review described the structure and main characteristics of the nasal cavity. The advantages, achievements and challenges of the nasal route use for medical purposes are discussed, with particular focus on vaccine delivery. Compelling evidences support the potentialities and safety of the nasal delivery of vaccines and drugs. This alternative route could become a solution for many unmet medical issues and also may facilitate and cheapen massive immunization campaigns or long-lasting chronic treatments. Nowadays, in spite of certain remaining skepticism, the field of nasal delivery of drugs and vaccines is growing fast, bolstered by current developments in nanotechnology, imaging and administration devices. A notable increase in the number of approved drugs for nasal administration is envisaged.